Construction using a hydraulic excavator for tunnels is possible! We have a track record of approximately 40 meters as ultra-long mirror reinforcement.
The "F-S Bolt" is a long steel pipe injection mirror bolt that can be constructed at a low cost compared to non-steel materials. Since the steel pipe has slits, it can be easily cut and removed as the face advances, allowing for construction with a hydraulic tunnel boring machine. It has a high shear strength compared to other materials, providing tensile resistance against face collapse, as well as expected shear resistance. 【Features】 ■ Can be constructed at a low cost compared to non-steel materials ■ The slits in the steel pipe allow for easy cutting and removal as the face advances ■ Being made of steel, it is easy to separate from the spoil during cutting and removal ■ Injection of polyurethane and cement-based materials is possible, and it can also be used as a drainage hole ■ By adjusting the presence of slits, it can also be constructed as a small-diameter long-length forepole *For more details, please refer to the PDF document or feel free to contact us.
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【Specifications】 ■Nominal outer diameter (inner diameter): 76.3 (65.9) mm ■Shear strength: 200KN or more ■Tensile strength (threaded part): 229KN ■Bending strength: 235N/mm2 ■Elastic modulus: 200,000Mpa ■Weight: 9kg/m *For more details, please refer to the PDF document or feel free to contact us.
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【Scope of Application】 ■ Applicable to gravelly soil, sandy soil, clayey soil, moderately hard rock, and low self-supporting collapsing ground. Application of techniques such as mirror reinforcement, long-length pre-support, and drainage is possible. *For more details, please refer to the PDF materials or feel free to contact us.
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Fujimori Industries will take a step towards transformation to make an even greater leap forward. We aim for our efforts to eventually become a significant wave, setting a new standard = benchmark that everyone aspires to. Please pay attention to our evolution and development.